Method of and apparatus for stranding elongate material

ABSTRACT

In a machine for stranding elongate material for example metallic wire, comprising a first support means for receiving spools of the material to be stranded, a rotary twisting component, and a second support means for receiving a take-up spool for the stranded product, said rotary twisting component is disposed within an enclosure, means is provided for creating at least a partial vacuum within the enclosure, and sealing means is mounted in a wall of said enclosure through which the stranded product leaving the rotary twisting component is led to the takeup spool. Said first support means may also be disposed within said enclosure.

[451 July 23,1974

[ METHOD OF AND APPARATUS FOR STRANDING ELONGATE MATERIAL [75] Inventor:Norman John Birch, Wordsley,

England [73] Assignee: National-Standard Company Limited,Worcestershire, England [22] Filed: Aug. 24, 1972 [21] Appl. No.:283,558

[30] Foreign Application Priority Data 9/l963 France 57/58.52

119,457 9/1958 U.S.S.R 57/58.52

Primary ExaminerDonald E. Watkins Attorney, Agent, or Firm-Johnson,Dienne, Emrich, Verbeck & Wagner [5 7 ABSTRACT In a machine forstranding elongate material for example metallic wire, comprising afirst support means for receiving spools of the material to be stranded,a rotary twisting component, and a second support means for receiving atake-up spool for the stranded product, said rotary twisting componentis disposed within an enclosure, means is provided for creating at leasta partial vacuum within the enclosure, and sealing means is mounted in awall of said enclosure through which the stranded product leaving therotary twisting component is led to the take-up spool. Said firstsupport means may also be disposed within said enclosure.

4 Claims, 3 Drawing Figures PATENTED JUL 2 31974 PATENIEUJUL23IHT4 SHEET2 OF 2 NQI ain.

ww gwm 5 Q@ NW METHOD OF AND APPARATUS FOR STRANDING ELONGATE MATERIALThis invention relates to apparatus for stranding elongate material.

A strand is made by twisting together a plurality of lengths offilamentary material and a rope is made by twisting together a pluralityof strands. Various kinds of machines are known for producing strands,for example high speed tubular stranding machines, bunchers andtwisters, and the twisting together of strands to form a rope may alsobe performed in similar machines.

In order to simplify the ensuing description the word stranding will beusedto include both the forming of strands from filamentary material andtheforming of ropes from strands, and a machine for making strands fromfilamentary material or rope from strands will be referred to as astranding machine.

The apparatus of this invention have been devised mainly for employmentin the stranding of metallic wire material and the remainder of thisspecification will be confined to a description of the stranding of suchmaterial. It is to be understood, however, that the apparatus of theinvention is applicable to the stranding of other filamentary material,for example natural fibrous material and fibrous material made fromsynthetic plastics material.

In the stranding of wire the speed at which the stranding machineoperates is limited by a number of factors, including the effect ofcentrifugal force on certain components of the machine, the effect ofcentrifugal force on the product, the design of the machine bearings,the generation of heat in components of the machineand in the product,and the noise generated by operation of the machine.

The present invention is concerned primarily with reducing the amount ofheat and noise generated in the stranding of wire in a strandingmachine. At the present time, steps taken to try to reduce the heatgenerated have the result of accentuating the noise, and vice versa. Agreat deal of the noise is generated aerodynamically by components ofthe machine and the product travelling through the air at high velocity.Considerable power is also consumed in driving components of the machineand the product through the air and the air pumping losses cause machinecomponents to heat up.

The noise problem can be dealt with by completely enclosing the machinewith a well-fitting guard which is lined with sound-absorbing material.Unfortunately, such a completely enclosing guard prevents air flowthrough the machine and, with the same air circulating around the insidethe-guard all the time, the machine components are quickly heated up toan unacceptable level. If vents are provided in the guard to allow theescape of some of the air flow through the machine, noise is alsoallowed to escape.

One way in which the twin problems of heat and noise generation couldpossibly be avoided in the operation of a stranding machine would be toenclose the machine in a sound-insulating guard and to provide the guardwith means for supplying air to and extracting air from the guard in aclosed circulation system. This closed circulating system would itselfhave to be soundproofed and would need to comprise means to cool the airextracted from the guard before returning it to the latter. Such asystem would be both space-consuming and expensive.

The present invention seeks to overcome in a simple way the problems ofheat and noise generation in the operation of a stranding machine.

According to the invention a machine for stranding elongate materialcomprises an enclosure, first support means, a plurality of supplyspools of elongate material to be stranded supported by the firstsupport means, a rotary twisting component disposed within the enclosurefor twisting the elongate material from the supply spools into a strand,second support means disposed outwardly of the enclosure, a take-upspool supported by said second support means for receiving the strand,means associated with the enclosure for creating at least a partialvacuum within the enclosure, and sealing means mounted in a wall of theenclosure through which the strand passes from the rotary twistingcomponent to the take-up spool.

When employing the machine of the invention the volume of noisetransmitted from the twisting component of the stranding machine and themoving wire to a person outside the enclosure is considerably reduced bythe existence of sub-atmospheric pressure within the enclosure.Consequently, it is not necessary for the walls of the enclosure to beefiiciently sound-proofed. The wastage of power consumed in circulatingair insidethe enclosure is also greatly reduced. This in turn leads to adecrease in the risk of the machine parts becoming overheated.

In the case of a tubular wire stranding machine in accordance with theinvention, said first support means may also be located in saidenclosure.

With double bunchers the rotary twisting component can either rotatearound said first or second support means. In a double bunchers inaccordance with this invention, those sections of the machine whichcarry the wire around the first support means are housed in saidenclosure.

Since leakage of air into the enclosure from the surroundings willinevitably take place in a stranding machine in accordance with theinvention, adequate pumping capacity will have to be provided tomaintain the partial vacuum in said enclosure when the machine is inoperation.

If lubricated members of the stranding machine, for example shaftbearings, are located within said enclosure, steps would have to betaken to prevent removal of lubricant through the air-extractingequipment. This could be done by hermetically sealing the lubricatedmembers from the interior of said enclosure. This difficulty can,however, be avoided in some cases by mounting items such as shaftbearings externally of said enclosure. Simple air seals would then beprovided where the shafts enter the enclosure.

If overheating of members of the stranding machine which are locatedwithin said housing is a problem, then cooling of these members may haveto be resorted to, for example by providing them with water or oilcooling systems.

The invention will now be described in greater detail, by way ofexample, with reference to the accompanying drawings, in which FIG. 1 isa schematic sectional side view of a first embodiment of a strandingmachine of the double buncher type in accordance with the invention,

FIG. 2 is a view similar to FIG. 1 of a tubular wire stranding machine,and

FIG. 3 is a sectional view of a sealing means employed in apparatus inaccordance with the invention for leading wire from an evacuated closedspace.

The machine shown in FIG. 1 comprises a frame 1 provided with alignedbearings 2, 3 in which a rotary twisting component consisting of tworotary heads 4, 5 is mounted. The heads 4, 5 comprise shafts 6, 7respectively, which are rotated in synchronism with one another byendless flexible drive members 8, 9, respectively, from a common driveshaft 10.

Mounted between the two heads 4, 5 and prevented from rotating therewithby suitable counterweights is a first support means, generallydesignated by the numeral 11. The latter comprises a housing 12 providedat opposite sides with aligned stub shafts 13, 14 which are received inbearings 15, 16, respectively, mounted in the heads 4, 5, the axes ofthe bearings l5, 16 being aligned with the axes of the bearings 2, 3.Four spools 17 of wire are rotatably mounted on shafts 18 within thehousing 12, the shafts 18 being disposed at right angles to the axes ofthe bearings 15, 16.

The stub shaft has a central axial hole 19 therethrough which serves asa stranding die for four wires 20 led therethrough from the spools 17.After passing through the die 19 the stranded wires pass around a pulley21 rotatably mounted on a shaft 22 in the head 4, around pulleys 23 and24 rotatably mounted at the peripheral edges of flanges 25 and 26,respectively, forming parts of the heads 4 and 5, respectively, around apulley 27 rotatably mounted on a shaft 28 in the head 5, and thenthrough an axial hole 29 in the head 5. The stranded wire is drawn fromthe hole 29 by a capstan 30 and is laid on to a spool 30a by atraversing mechanism 31, the spool 30a being mounted in a second supportmeans 32.

The items so far described are standard components of a wire strandingmachine of a double buncher type. In operation of the machine, rotationof the shaft 10 causes synchronised rotation of the heads 4, 5 aroundthe housing 1 1 to effect stranding of the wires 20 drawn 3 from thespools 17 by the take-up spool 30a.

In the machine shown in FIG. 1, the twisting component consisting of theheads 4, 5 and the first support means 11 are enclosed in a cylindricalair-tight casing 33, the casing axis being in substantial alignment withthe axes of the bearings 2, 3. The casing 33 has a pcripheral wall 34and end walls 35, 36, the latter being provided with centrally disposedholes'37, 38 for passage therethrough of the shafts 6 and 7 of the heads4 and 5. Annular air-tight seals 39 and 40 are mounted in the holes 37,38, respectively, these seals providing an air-tight seal between thestationary end walls 35, 36 of the casing 33 and the rotary heads 4, 5.The peripheral wall 34 of the casing is made in at least two partshinged together by means of hinges 41 to afford easy access to the partsof the stranding machine located within the casing 33.

An outlet opening 42 is provided in the casing 33, which opening isconnectible to a vacuum pump 43 by a conduit 44. When the pump 43 is setin motion the interior of the casing 33 is partially evacuated. Entry ofair into the casing through the hole 29 can be prevented to a largedegree by suitably dimensioning the hole 29. For example the hole 29 mayhave a diameter of from 0.05 to 0.12 mm greater than the diameter of thestranded wire passing therethrough. Depending on the wire diameter, asuitable length for the hole 29 is from 7.5 to 15.0 cms. The hole 29 maybe provided in a separate sleeve 45 (see FIG. 3) which is mounted in theshaft 7 of the head 5. A range of different sleeves 45 suitable fordifferent wire diameters can then be supplied with the machine.

By partially evacuating the casing 33, the noise emitted by the rotarytwisting component 4, 5 and by the wires 20 in moving from the spools 17to the hole 29 is to a large extent cut off from anoperative'supervising the machine. There is no need for the casing 33 tobe made of a sound-insulating material. Instead, it can be made of asound material having good heat-conducting properties, for example sheetmetal, so that heat radiated from the moving components within thecasing 33 can be transmitted through the casing and thus preventoverheating of the components within the casing.

FIG. 2 shows a tubular wire stranding machine hav ing two sections 50,51 each provided with a conventional tube 52 within which is a firstsupport means in the form of cradles 53 carrying spools 54 of wire. Thetubes 52 are'driven in synchronism with one another by a comon driveshaft 55 which is itself driven by an electric motor 56. Wires 57 fromthe spools 54 pass through a stranding die 58 and thence to a take-updevice 59 for the stranded wire, the device 59 including a take-up spool60. The parts so far described are standard items of a conventionaltubular wire stranding machine.

Around each of the tubes 52 there is arranged a stationary cylindricalcasing 61, for example of sheet metal. The ends of the casing 61 aresealed in an airtight manner to frame members 62 of the machine in whichthe tubes 52 are rotatably supported. Each casing 61 has an outletopening 63 which is connectible to a vacuum pump (not shown) so that theinterior of the casing can be partially evacuated when the machine is inoperation. As in the case of the machine of FIG. 1, each of the casings61 is preferably made in a plurality of parts, suitably hinged together,in order to afford easy access to the components within the casing.

In both of the machines described above with reference to the drawings,there will inevitably be a certain leakage of air into thepartially'evacuated casings of the machines. This is of no consequenceprovided that adequate pumping capacity is provided to maintainevacuation of the casing at a suitable level.

What is claimed is:

l. A machine for stranding elongate material comprising, an enclosure,first support means, a plurality of supply spools of elongate materialto be stranded supported by said first support means, a rotary twistingcomponent disposedwithin said enclosure for twisting the elongatematerial fromsaid supply spools into a strand, second support meansdisposed outwardly of the enclosure, a take-up spool supported by saidsecond support means for receiving said strand, means associated withsaid enclosure for creating at least a partial vacuum within saidenclosure, and sealing means mounted in a wall of said enclosure throughwhich said strand passes from the rotary twisting component to saidtake-up spool.

2. A machine as claimed in claim 1, in which said first support means isalso disposed within said enclosure.

3. A machine as claimed in claim 1, in which said enclosure is a casingmade of sheet metal.

4. A machine as claimed in claim 3, in which said casing is made of aplurality of parts hinged together.

1. A machine for stranding elongate material comprising, an enclosure,first support means, a plurality of supply spools of elongate materialto be stranded supported by said first support means, a rotary twistingcomponent disposed within said enclosure for twisting the elongatematerial from said supply spools into a strand, second support meansdisposed outwardly of the enclosure, a take-up spool supported by saidsecond support means for receiving said strand, means associated withsaid enclosure for creating at least a partial vacuum within saidenclosure, and sealing means mounted in a wall of said enclosure throughwhich said strand passes from the rotary twisting component to saidtake-up spool.
 2. A machine as claimed in claim 1, in which said firstsupport means is also disposed within said enclosure.
 3. A machine asclaimed in claim 1, in which said enclosure is a casing made of sheetmetal.
 4. A machine as claimed in claim 3, in which said casing is madeof a plurality of parts hinged together.